Procedural texture is not visible in render
The problem is with the 'Add Shader' node before the color ramp node. This is because the 'fac' input to the color ramp node should be a value. Instead the 'Add Shader' node gives a shader which the colorramp node can't understand properly.Also, ideally the 'Add Shader' node should take shaders as inputs instead of color or values.


In the place of the 'Add Shader' node, use 'Math' node and change it to add.Math node can be accessed by Converter>Math



The node setup will look something like this.